Reduction of metals



Patented Dec. 23, 1924.-

UNITED STTES WALTER BIRKETT HAMILTON,

. NORFOLK,

REDUCTION No Drawing. Application filed May 17,

To all whom) it may concern:

Be it known that we, WALTER BIRKETT HAMILTON, a subject of the King of England, residing at Lancaster, England, and

5 FEReUs REID, a citizen of the United States, residing at Norfolk, Virginia, have invented certain new and useful Improvements in the Reduction of Metals, of which the following is a specification.

Our invention relates to the reduction of metals from ores and it consists of certain novel processesset forth in the claims concluding this specification.

It is now known that chromium ore (chromite) and ores containing oxides of other metals, as, for example, tungsten, nickel,

manganese, or the like, may be dissolved in a suitable molten reception slag in the presence of a suitable reducing agent, such, for example, as silicon; and that the metal content thereof will descend beneath the slag, While the other components of the ore will be retained in the molten slag. Particulars and variations of this process, of which our present invention is an improvement, are described in Patent No. 1,482,289 to Hamilton and Evans, patented October 17, 1922, to which reference ismade, and need not be repeated here. We have discovered that instead of employing silicon as the said reducing agent, oxide of silicon (sand) may be employed in the presence of a reducing agent for said oxide of silicon, such, for example, as carbon.

The following is an example of the practice of our process, although our invention is not limited thereto or thereby: One hundred (100 pounds of iron may be melted in any suita le furnace (as, for example, an electric furnace lined with magnesite).

After the removal of the slag first formed,

a reception slag composed of eighty-four (84:) pounds of lime and fluor-spar and orty-two (42) pounds of oxide of. silicon 45 (sand) may be formed on top of the molten 1ron. Fusion is assisted by adding to and dissolving in this slag, say, one hundred and on LANCASTER, ENGLAND, AND FERGUS REID, 0F

VIRGINIA.

on METALS.

1923. Serial No. 639,697.

twelve (112) pounds of chromite. When the temperature of the slag reaches, say, above 1450 0., carbon is introduced into, or added to the surface of the molten slag in small quantities until the chromium oxide is exhausted by being reduced to metal, which descends into the molten metal beneath the slag. Subsequent additional charges of chromite may be added and similarly reduced by the addition of further carbon, the temperature of the slag being maintained throughout the operation.

Various modifications and changes may be made in the process without departing from the spirit of our invention and without exceding the scope of our claims.-

What we claim is:

1. The process of reducing metal oxide and separating it from ore, which consists in adding a reducing agent for oxide of silicon to a molten reception slag containing oxide of silicon and oxide of the metal to be reduced.

2. The process of reducing metal oxide and separating it from ore, which consists in adding cabon to a molten reception slag containing oxide of silicon and oxide of the metal to be reduced.

-3. The process of reducing chromite and separating the metal content from the ore, which consists in adding a reducing agent for oxide of silicon to a molten reception slag containing oxide of silicon and the chromite to be reduced.

4:. The process of reducing chromite and separating the metal content from the ore, which consists in adding carbon to a molten reception slag containing oxide of silicon and the chromite to be reduced.

5. The process of making iron alloys which consists in charging a furnace with iron, melting the same, forming a slag thereon containing oxide of silicon, and ore containing the metal to be alloyed with the iron and then adding a reducing agent for the oxide of silicon.

6. The process of making iron alloys which consist in charging a furnace with iron, melting the same, forming a slag thereon containing oxide of silicon, and ore containing the metal to be alloyed with the iron and then adding carbon.

7. The process of making rust-resisting metal which consists in charging a furnace with iron, melting the same, forming a slag thereon containing oxide of silicon and.

chromite and then adding a reducing agent no for the oxide of silicon.

8. The process of making rust-resisting metal which consists in charging a furnace With iron, melting the same, forming a slag thereon containing oxide of silicon and chro- 115 mite and then adding carbon.

WALTER BIRKETT HAMILTON. FERGUS REID. 

